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Interactive effects of microplastics and typical pollutants on the soilplant system:a mini-review
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作者 Shahid Iqbal Jianchu Xu +4 位作者 Heng Gui Dengpan Bu Sulaiman Almwarai Alharbi Sehroon Khan Sadia Nadir 《Circular Agricultural Systems》 2024年第1期51-56,共6页
Although research on microplastics(MPs)interactions with other soil pollutants is increasingly becoming available,most studies do not consider risks to soil fertility or plant growth.This review aims:1)to summarize th... Although research on microplastics(MPs)interactions with other soil pollutants is increasingly becoming available,most studies do not consider risks to soil fertility or plant growth.This review aims:1)to summarize the results of current studies on interactions between MPs,heavy metals,and organic pollutants;and 2)subsequently evaluate risks to the soil-plant nexus.Available-literature shows that polypropylene,polyethylene and polylactic acid increase cadmium(Cd)bioavailability and subsequently reduce root growth.Such effects are not evident in sandy or clay soils due to the formation of CdCO3 and iron-oxide by altered bacterial communities that stabilize Cd contamination.Chronic instead of short-term exposure to polystyrene in copper(Cu)-polluted soils decreases crop yield.With coexistence of MPs and lead(Pb)in soil,the uptake of Pb in crops increases,causing altered malondialdehyde content and superoxide dismutase and guaiacol peroxidase activities.Moreover,co-toxicity of polystyrene or polytetrafluoroethylene with arsenic(As)decreases root biomass,photosynthesis rate and the chlorophyll-a content.In alkaline soil,polyvinyl-chloride could decrease the bioavailability of MeHg due to changes in the abundance of Proteobacteria,and Firmicutes.We also found strong interactions between MPs and organic pollutants.Polystyrene decreases negative impacts of sulfamethazine on bacterial diversity,and structure in soil.Polyethylene,polyvinyl-chloride and polystyrene have a strong adsorption capacity for 17β-estradiol.This implies that 17β-estradiol toxicity can be reduced by these MPs.At low concentrations,polyethylene,polypropylene,and polystyrene have low affinity to diazepam.In conclusion,serious ecological risks are associated with MPs and other pollutants'interactions to soil-plant system. 展开更多
关键词 POLYSTYRENE implies SYSTEM
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Allometric models for estimating aboveground biomass and carbon in Faidherbia albida and Prosopis africana under agroforestry parklands in drylands of Niger
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作者 Massaoudou Moussa Larwanou Mahamane 《Journal of Forestry Research》 SCIE CAS CSCD 2018年第6期1703-1717,共15页
This study developed allometric models to estimate aboveground biomass and carbon of Prosopis africana and Faidherbia albida. The destructive method was used with a sample of 20 trees per species for the two parkland ... This study developed allometric models to estimate aboveground biomass and carbon of Prosopis africana and Faidherbia albida. The destructive method was used with a sample of 20 trees per species for the two parkland sites. Linear regression with log transformation was used to model aboveground biomass according to dendrometric parameters. Error analysis, including mean absolute percentage of error(MAPE) and root mean square of error(RMSE), was used to select and validate the models for both species. Model 1(biomass according to tree diameter) for P. africana and F. albida were considered more representative. The statistical parameters of these models were R2 = 0.99, MAPE 0.98% and RMSE1.75% for P. africana, and R2 = 0.99, MAPE 1.19%,RMSE 2.37% for F. albida. The average rate of carbon sequestered was significantly different for the two species(P ≤ 0.05). The total amount sequestered per tree averaged0.17 × 10-3 Mg for P. africana and 0.25 × 10-3 Mg for F. albida. These results could be used to develop policies that would lead to the sustainable management of these resources in the dry parklands of Niger. 展开更多
关键词 Aboveground biomass AGROFORESTRY Allometric models CARBON NIGER Soudano-sahelian
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Supplementation with sodium butyrate improves growth and antioxidant function in dairy calves before weaning 被引量:13
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作者 Wenhui Liu ALa Teng Zhu La +4 位作者 Alexander Evans Shengtao Gao Zhongtang Yu Dengpan Bu Lu Ma 《Journal of Animal Science and Biotechnology》 SCIE CAS CSCD 2021年第1期305-313,共9页
Background: There is increasing research interest in using short-chain fatty acids(SCFAs) including butyrate as potential alternatives to antibiotic growth promoters in animal production. This study was conducted to e... Background: There is increasing research interest in using short-chain fatty acids(SCFAs) including butyrate as potential alternatives to antibiotic growth promoters in animal production. This study was conducted to evaluate the effects of supplementation of sodium butyrate(SB) in liquid feeds(milk, milk replacer, and the mixture of both)on the growth performance, rumen fermentation, and serum antioxidant capacity and immunoglobins in dairy calves before weaning. Forty healthy female Holstein calves(4-day-old, 40 ± 5 kg of body weight) were housed in individual hutches and randomly allocated to 1 of 4 treatment groups(n = 10 per group) using the RAND function in Excel. The control group was fed no SB(SB0), while the other three groups were supplemented with 15(SB15),30(SB30), or 45(SB45) g/d of SB mixed into liquid feeds offered. The calves were initially fed milk only(days 2 to 20), then a mixture of milk and milk replacer(days 21 to 23), and finally milk replacer only(days 24 to 60).Results: The SB supplementation enhanced growth and improved feed conversion into body weight gain compared with the SB0 group, and the average daily gain increased quadratically with increasing SB supplementation. No significant effect on rumen pH;concentrations of NH_3-N, individual and total VFAs;or acetate:propionate(A:P) ratio was found during the whole experimental period. Serum glutathione peroxidase activity increased linearly with the increased SB supplementation, while the serum concentration of maleic dialdehyde linearly decreased. Serum concentrations of immunoglobulin A, immunoglobulin G, or immunoglobulin M were not affected by the SB supplementation during the whole experimental period.Conclusions: Under the conditions of this study, SB supplementation improved growth performance and antioxidant function in pre-weaned dairy calves. We recommended 45 g/d as the optimal level of SB supplementation mixed into liquid feeds(milk or milk replacer) to improve the growth and antioxidant function of dairy calves before weaning. 展开更多
关键词 Antioxidant activity CALF Immune function Sodium butyrate
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Current re-vegetation patterns and restoration issues in degraded geological phosphorus-rich mountain areas:A synthetic analysis of Central Yunnan, SW China 被引量:2
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作者 Kai Yan Sailesh Ranjitkar +4 位作者 Deli Zhai Yunju Li Jianchu Xu Bo Li Yang Lu 《Plant Diversity》 SCIE CAS CSCD 北大核心 2017年第3期140-148,共9页
China has the largest area of inland geological phosphorus-rich(GPR) mountains in the world, where vegetation restoration is key to safeguarding the environment. We reviewed the published literature and collected new ... China has the largest area of inland geological phosphorus-rich(GPR) mountains in the world, where vegetation restoration is key to safeguarding the environment. We reviewed the published literature and collected new data in order to analyze re-vegetation patterns and the status of plant communities in central Yunnan. The aim of our analysis was to suggest future improvements to restoration strategies in GPR mountain regions. Our results showed that spontaneous recovery was the most widespread type of restoration. N-fixing species such as Coriaria nepalensis and Alnus nepalensis play a vital role in succession. In the past, monoculture tree plantation was the primary method used in afforestation activities in central Yunnan; in recent years however, several different methods of restoration have been introduced including the use of agroforestry systems. For practical restoration, we found that spontaneous recovery was capable of delivering the best results, but that during its early stages, restoration results were affected by several factors including erosion risk, the origin of propagates and environmental variation. In contrast, methods employing human-made communities performed better in their early stages, but were constrained by higher costs and vulnerability to degradation and erosion. The use of N-fixing species such as A. nepalensis and Acacia mearnsii in plantations were unsuccessful in restoring full ecosystem functions. The success of restoration activities in GPR mountain regions could be improved through the following measures:(1) developing a better understanding of the respective advantages and disadvantages of current natural and human-engineered restoration approaches;(2) elucidating the feedback mechanism between phosphorus-rich soil and species selected for restoration, especially N-fixing species;(3) introducing market incentives aimed at encouraging specific restoration activities such as agroforestry, and improving the industry value chain. 展开更多
关键词 Systematic review Dianchi Lake Fuxian Lake Natural restoration Human engineered restoration Floristic similarity
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Opportunity Costs of Emissions Caused by Land-Use Changes 被引量:2
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作者 S. Suyanto Andree Ekadinata +1 位作者 Muhammad Sofiyuddin Arif Rahmanullah 《Open Journal of Forestry》 2014年第1期85-90,共6页
Amid the euphoria of Reducing Emissions from Deforestation and Forest Degradation (REDD) and REDD+ discussions, the expectations of large financial gains raise the interest of all. A country, however, will only enjoy ... Amid the euphoria of Reducing Emissions from Deforestation and Forest Degradation (REDD) and REDD+ discussions, the expectations of large financial gains raise the interest of all. A country, however, will only enjoy REDD benefits if the cost of REDD is lower than the benefit. The opportunity cost analysis is an effective tool for assessing the feasibility of REDD+ since the largest portion of costs associated with REDD+ and can help to identify fair compensation for those who change their land use. The opportunity cost analysis has been exercised in Tanjung Jabung Barat (Tanjabar) district-Indonesia to examine the economic-feasibility of carbon emission reduction under different type carbon price scenarios. This study reveals a sharp decline of land-use systems with high carbon-stock and low profitability is obvious. On mineral soil, low carbon-stock and high profitability (mostly oil palm) has increased rapidly, especially in the period 2000-2009. It has become the dominant land-use system. The low-to-medium carbon stock and medium profitability land-use category increased from 1990 to 2005 but declined from 2005 to 2009. The low carbon-stock and low profitability category was constant and the proportion of the area was below 15%. The ex-ante analysis in predicting the potential for future emissions reduction in Tanjabar through REDD+ approaches shows that the cumulative emission of Tanjabar in 2020 is estimated at 61.91 Mg CO2-eq/Ha.Year, while the reduced emission by excluding all land use conversion below $5 threshold is estimated at 51.71 Mg CO2-eq/Ha.Year. This means that there is a potential for 16% emission reduction using $5/ton CO2-eq incentive. Another important finding in this study is that if the price of carbon increases by double to $10, the amount of reduced emission does not change much. This can use as a basis for determining the right amount of incentive for trade-off between economic profitability and climate change mitigation effort in Tanjabar using REDD+ scheme both at seller and buyer perspectives. 展开更多
关键词 OPPORTUNITY COST LAND Use Change Carbon Emission REDDS
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Assessment of Profitability of Land Use Systems in Tanjung Jabung Barat District, Jambi Province, Indonesia 被引量:2
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作者 Muhammad Sofiyuddin Arief Rahmanulloh S. Suyanto 《Open Journal of Forestry》 2012年第4期252-256,共5页
The purpose of the research was to compare the profitability of existing land uses in Tanjung Jabung Barat, Jambi province, Indonesia, for formulating a strategy to reduce emissions from deforestation and de-gradation... The purpose of the research was to compare the profitability of existing land uses in Tanjung Jabung Barat, Jambi province, Indonesia, for formulating a strategy to reduce emissions from deforestation and de-gradation (REDD). Net Present Value was used for comparing profits of different types of investment (e.g. different type of land use). Rapid Rural Appraisal was used to gather information on farm budget data for each land use, including prices, production, labor and other input. The results of the profitability analysis showed that all land uses, both on mineral soil and peat land, were profitable. Oil palm, both in large plantations and smallholder gardens, was the most profitable land-use system. However, the profitability of smallholder oil palm on peatland was lower than on mineral soils yet oil palm was still more competitive than rubber on mineral soils. The competitiveness of mixed gardens with oil palm was higher on peatland and the threat of converting other land uses to oil palm was higher on mineral soil than on peat. For crop systems, irrigated paddy had the highest profitability. 展开更多
关键词 PROFITABILITY NPV LAND USE System REDD+ Indonesia
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Using leaf area index(LAI) to assess vegetation response to drought in Yunnan province of China 被引量:4
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作者 Kwangchol KIM WANG Ming-cheng +3 位作者 Sailesh RANJITKAR LIU Su-hong XU Jian-chu Robert J.ZOMER 《Journal of Mountain Science》 SCIE CSCD 2017年第9期1863-1872,共10页
Climatic extremes such as drought have becoming a severe climate-related problem in many regions all over the world that can induce anomalies in vegetation condition. Growth and CO2 uptake by plants are constrained to... Climatic extremes such as drought have becoming a severe climate-related problem in many regions all over the world that can induce anomalies in vegetation condition. Growth and CO2 uptake by plants are constrained to a large extent by drought.Therefore, it is important to understand the spatial and temporal responses of vegetation to drought across the various land cover types and different regions. Leaf area index(LAI) derived from Global Land Surface Satellite(GLASS) data was used to evaluate the response of vegetation to drought occurrence across Yunnan Province, China(2001-2010). The meteorological drought was assessed based on Standardized Precipitation Index(SPI)values. Pearson's correlation coefficients between LAI and SPI were examined across several timescales within six sub-regions of the Yunnan. Further, the drought-prone area was identified based on LAI anomaly values. Lag and cumulative effects of lack of precipitation on vegetation were evident, with significant correlations found using 3-, 6-, 9-and 12-month timescale. We found 9-month timescale has higher correlations compared to another timescale.Approximately 29.4% of Yunnan's area was classified as drought-prone area, based on the LAI anomaly values. Most of this drought-prone area was distributed in the mountainous region of Yunnan.From the research, it is evident that GLASS LAI can be effectively used as an indicator for assessing drought conditions and it provide valuable information for drought risk defense and preparedness. 展开更多
关键词 MODIS Leaf area index distribution Standardized Precipitation Index(SPI) Drought Yunnan
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Lessons Learned and Future Challenges for Integrated and Participatory Approaches to Mountain Research——Conclusions from the Mountain Symposium and this Special Issue
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作者 Franz Heidhues Karl Stahr +2 位作者 Uwe Jens Nagel David Thomas Andreas Neef 《Journal of Mountain Science》 SCIE CSCD 2006年第4期347-354,共8页
The International Symposium ‘Towards Sustainable Livelihoods and Ecosystems in Mountainous Regions', held in Chiang Mai from 7-9 March 2006 (hereafter referred to as ‘Mountain Symposium'), brought together a wea... The International Symposium ‘Towards Sustainable Livelihoods and Ecosystems in Mountainous Regions', held in Chiang Mai from 7-9 March 2006 (hereafter referred to as ‘Mountain Symposium'), brought together a wealth of experience from mountain research and development in four continents. Some of its highlights are presented in this Special Issue. If one were to choose a 'leitmotif that would best capture the present state of knowledge in mountain research, it would be recognizing heterogeneity, complexity, interdependency, and learning how to deal with it. We are in the middle of a learning process and it is important to remember Rod Lefroy's statement in the panel discussion of the Mountain Symposium: "perfection is the enemy of progress" (Lefroy 2006). 展开更多
关键词 山区开发 国际研讨会 专刊 可持续民生 可持续生态系统 综合研究 分担研究
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Integrated and Participatory Research Approaches towards Sustainable Livelihoods and Ecosystems in Mountainous Regions
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作者 Andreas Neef Franz Heidhues +2 位作者 Karl Stahr David Thomas Pittaya Sruamsiri 《Journal of Mountain Science》 SCIE CSCD 2006年第4期271-275,共5页
Mountainous regions cover about 27 per cent of the world's land surface and are home to some 22 per cent of the global population (UNEP 2002). A much greater number of people depend on mountain environments for a w... Mountainous regions cover about 27 per cent of the world's land surface and are home to some 22 per cent of the global population (UNEP 2002). A much greater number of people depend on mountain environments for a wide range of services, including clean water, energy, timber, biodiversity, recreation, and protection from environmental hazards, such as landslides and floods. At the same time, mountain areas are extremely vulnerable ecosystems and under continuous threat of environmental degradation due to such diverse factors as climate change, extraction of their rich natural resources, high population pressure, and insecure and inequitable resource ownership. Mountain people are often among the most marginalized groups in society. Political and social discrimination is largely accompanied by pervasive poverty and food insecurity. A recent FAO study on vulnerability in mountains found that as many as 245 million people in the mountains of developing and transition countries are at risk of, or actually suffering from hunger and food insecurity (Diouf 2006). At the same time, mountain areas are major sources and production areas of narcotic plants, such as opium poppy in Afghanistan and Myanmar, qat in Yemen and Ethiopia, and coca in Colombia, Peru and Bolivia. The remoteness and frequent position of mountain regions along disputed political and ethnic borders also make them more prone to armed conflict. It was estimated that between 1946 and 2ool, around 41 per cent of mountainous areas experienced violent conflicts compared to 26 per cent of non-mountain regions (UNEP 2002). On the other hand, mountainous regions are treasures of biological and agricultural diversity. Perhaps no other life zone contains such high degree of variation between habitats and ecosystems as mountains (Denniston 1995). Genetic diversity in agricultural resources also tends to be higher in mountainous regions than in the lowlands, largely due to ethnic and cultural diversity and the extreme micro-variability of environmental conditions. Mountain communities in the Andes region are reported to conserve more than 150 distinct potato varieties, while highland farmers in Central Africa cultivate mixtures of 30 bean varieties simultaneously (UNEP 2002). 展开更多
关键词 山区 可持续民生 可持续农业-生态系统 综合研究法 参与式研究法 多学科研究
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Cutting of Phragmites australis as a lake restoration technique: Productivity calculation and nutrient removal in Wuliangsuhai Lake, northern China
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作者 Jan Felix Kobbing Niels Thevs Stefan Zerbe 《Research in Cold and Arid Regions》 CSCD 2016年第5期400-410,共11页
Reed is one of the most frequent and dominant species in wetlands all over the world, with common reed (Phragmites australis (Cav.) Trin. ex Steud.) as the most widely distributed species. In many wetlands, P. aus... Reed is one of the most frequent and dominant species in wetlands all over the world, with common reed (Phragmites australis (Cav.) Trin. ex Steud.) as the most widely distributed species. In many wetlands, P. australis plays a highly ambivalent role. On the one hand, in many wetlands it purifies wastewater, provides habitat for numerous species, and is a potentially valuable raw material, while on the other hand it is an invasive species which expands aggressively, prevents fishing, blocks ditches and waterways, and builds monospecies stands. This paper uses the eutrophic reed-swamp of Wuliangsuhai Lake in Inner Mongolia, northern China, as a case to present the multiple benefits of regular reed cutting. The reed area and aboveground biomass production are calculated based on field data. Combined with data about water and reed nutrient content, the impact of reed cutting on the lake nutrient budget (N and P) is investigated. Currently, at this lake around 100,000 tons of reed are harvested in winter annually, removing 16% and 8% of the total nitrogen and phosphorus influx, respectively. Harvesting all available winter reed could increase the nutrient removal rates to 48% and 24%, respectively. We also consider the effects of summer harvesting, in which reed biomass removal could overcompensate for the nutrient influx but could potentially reduce reed regrowth. 展开更多
关键词 common reed ecosystem restoration water purification reed utilization wetland ecosystem DRYLAND
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Source of mycorrhizal inoculum influences growth of Faidherbia albida seedlings
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作者 Emiru Birhane Mengsteab Hailemariam +3 位作者 Girmay Gebresamuel Tesfay Araya Kiros Meles Hadgu Lindsey Norgrove 《Journal of Forestry Research》 SCIE CAS CSCD 2020年第1期313-323,共11页
Poor land use management and practice inhibit the growth and establishment of tree seedlings in dryland areas.We assessed arbuscular mycorrhizal fungi(AM)status of Faidherbia albida(Del.)A.Chev.trees grown on differen... Poor land use management and practice inhibit the growth and establishment of tree seedlings in dryland areas.We assessed arbuscular mycorrhizal fungi(AM)status of Faidherbia albida(Del.)A.Chev.trees grown on different land uses.We quantified the growth and nutrient uptake of F.albida seedlings inoculated with AM from different sources.These efforts were based on soil and fine root samples from the rhizosphere soils of F.albida trees.AM root colonization was determined using the gridline intersect method.Spores were extracted by the wet sieving and decanting method and identified to genus level.The seedling experiment had a completely randomized onefactorial design with four treatments and five replications.Faidherbida albida seedlings were grown in a greenhouse.All in situ F.albida trees were colonized by AM fungi.AM root colonization of F.albida trees was significantly higher(P<0.0086)in area exclosures than on lands used for grazing or cultivation.Spore abundance was significantly higher(P<0.0014)in area exclosures followed by cultivated land and grazing land.Glomus was the dominant genus in all land-uses.AM-inoculated F.albida seedlings grew better(P<0.05)than non-inoculated controls.Seedlings inoculated with AM from area exclosure had significantly(P<0.05)higher growth and nutrient uptake than those inoculated with AM from grazing and cultivated land.This emphasizes the importance of the native soil AM potential for better establishment of seedlings to achieve optimum plant growth improvement and assist in rehabilitation of degraded arid lands. 展开更多
关键词 Spore abundance AM colonization Inoculum types Land-use types Nutrient uptake Growth parameters
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Mapping Vulnerability to Climate Change in Malawi: Spatial and Social Differentiation in the Shire River Basin
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作者 Jeanne Yekeleya Coulibaly Cheikh Mbow +3 位作者 Gudeta Weldesemayat Sileshi Tracy Beedy Godfrey Kundhlande John Musau 《American Journal of Climate Change》 2015年第3期282-294,共13页
This article analyses vulnerability to climate related shocks across five districts in the shire river basin of Malawi. The analysis employs an indicator approach that integrates biophysical and socio-economic indices... This article analyses vulnerability to climate related shocks across five districts in the shire river basin of Malawi. The analysis employs an indicator approach that integrates biophysical and socio-economic indices. Principal component statistical analysis was used to calculate an index for adaptive capacity, sensitivity and exposure to climate impact for each of the five districts. These indices were aggregated to develop a vulnerability index differentiated also by gender for the surveyed districts. The results showed that Chikwawa, Machinga and Blantyre appear to be more vulnerable to climate related shocks compared with Mwanza and Zomba. Women in Chikwawa are also found to be the most susceptible to the climate hazards impacts. To reduce vulnerability to climate impact, the study suggests that the national adaptation strategies adopted by the government should be mainstreamed into specific local adaptation actions that can be accessible and adopted by the community. Specific emphasis should be given to the improvement of women’s welfare through better access to productive assets and resources. 展开更多
关键词 CLIMATE Change VULNERABILITY Principal Component Analysis Malawi Shire RIVER BASIN
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Review of Innovative Agricultural Market Creation in Africa and the Study of Three-tier Model for Soybean Development and Promotion in Kenya
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作者 Jonas Nwankwo Chianu Bernard Vanlauwe +2 位作者 Akinwumi Adesina Justina Nwanganga Chianu NteranyaSanginga 《Journal of Life Sciences》 2010年第3期43-51,共9页
Agricultural market creation was critical for rural growth in Africa. How to achieve this based on crops other than major staples (e.g. maize) and traditional export crops (e.g., tea, coffee, cotton) remained a pr... Agricultural market creation was critical for rural growth in Africa. How to achieve this based on crops other than major staples (e.g. maize) and traditional export crops (e.g., tea, coffee, cotton) remained a problem since most African countries did not give them policy attention. This study used a three-tier-model, developed based on successful strategies in Nigeria and Zimbabwe, to develop multi-level soybean market creation in Kenya. Data were from secondary sources, formal and informal interviews, farm-level data, and participant observations. Analysis was carried out using Microsoft Excel and SPSS. Result showed increasing in farmers' confidence to produce, process, consume, and sell more soybeans than before. Trained farmers' groups were developing new soybean products for cash, poverty reduction and improvements in livelihoods. Net returns had been increased from 4 to 14 times from processed products. Selected farmers' groups had begun to supply large-scale processors with soybean grains, substituting imports. The overall project's impact on number of participating farmer groups and the actual land area devoted to soybean cultivation ranged from a factor of 2.3 to a factor of 77.4 between the long rainy seasons of 2005 / 2006 and the short rainy seasons of 2009. Farmers had given testimonies on live improvements. 展开更多
关键词 Agricultural market CREATION three-tier-model SOYBEAN AFRICA Kenya.
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Multiscalar Geomorphometric Generalization for Soil-Landscape Modeling by Random Forest: A Case Study in the Eastern Amazon
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作者 Cauan Ferreira Araújo Raimundo Cosme de Oliveira Junior Troy Patrick Beldini 《Journal of Geographic Information System》 2021年第4期434-451,共18页
Multiscalar topography influence on soil distribution has a complex pattern that is related to overlay of pedological processes which occurred at different times, and these driving forces are correlated with many geom... Multiscalar topography influence on soil distribution has a complex pattern that is related to overlay of pedological processes which occurred at different times, and these driving forces are correlated with many geomorphologic scales. In this sense, the present study tested the hypothesis whether multiscale geomorphometric generalized covariables can improve pedometric modeling. To achieve this goal, this case study applied the Random Forest algorithm to a multiscale geomorphometric database to predict soil surface attributes. The study area is in phanerozoic sedimentary basins, in the Alter do Ch<span style="white-space:nowrap;">&#227;</span>o geological formation, Eastern Amazon, Brazil. The multiscale geomorphometric generalization was applied at general and specific geomorphometric covariables, producing groups for each scale combination. The modeling was run using Random Forest for A-horizon thickness, pH, silt and sand content. For model evaluation, visual analysis of digital maps, metrics of forest structures and effect of variables on prediction were used. For evaluation of soil textural classifications, the confusion matrix with a Kappa index, and the user’s and producer’s accuracies were employed. The geomorphometry generalization tends to smooth curvatures and produces identifiable geomorphic representations at sub-watershed and watershed levels. The forest structures and effect of variables on prediction are in agreement with pedological knowledge. The multiscale geomorphometric generalized covariables improved accuracy metrics of soil surface texture classification, with the Kappa Index going from 43% to 62%. Therefore, it can be argued that topography influences soil distribution at combined coarser spatial scales and is able to predict soil particle size contents in the studied watershed. Future development of the multiscale geomorphometric generalization framework could include generalization methods concerning preservation of features, landform classification adaptable at multiple scales. 展开更多
关键词 Digital Soil Mapping Upscaling Machine Learning Random Forest Algorithm Multiscale Geomorphometric Generalization
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Key biodiversity recommendations from the 2021 FTA Scientific Conference
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作者 FTA Scientific Steering Committee 《Circular Agricultural Systems》 2021年第1期87-88,共2页
Nature is in peril.The Convention on Biological Diversity(CBD)as the largest multilateral treaty on the protection of global biodiversity must play a significantly expanded role in the next decade of biodiversity poli... Nature is in peril.The Convention on Biological Diversity(CBD)as the largest multilateral treaty on the protection of global biodiversity must play a significantly expanded role in the next decade of biodiversity policy development and implementation if we wish to halt and reverse accelerating biodiversity losses.From the 22nd–24th of June 2021,nearly 400 on-site and online participants gathered at the FTA Scientific Conference in Kunming,China as part of the buildup to the 15th meeting(COP15)of the CBD.From the technical and plenary sessions,12 recommendations emerged to strengthen the capacity of the CBD and safeguard the planet's wildlife.Participants urge all stakeholders,particularly government actors in attendance at CBD COP15 in Kunming in October 2021,to heed the warnings of experts in attendance at the FTA Scientific Conference to accelerate and intensify efforts to conserve diverse lifeforms and maintain healthy ecosystems by incorporating these 12 recommendations into the post-2020 global biodiversity framework of the CBD. 展开更多
关键词 FTA PLANET MAINTAIN
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Root symbioses as belowground C pumps:a mitigation strategy against rising CO_(2)levels
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作者 Peter E.Mortimer James Hammond +2 位作者 Kevin D.Hyde Heng Gui Jianchu Xu 《Circular Agricultural Systems》 2021年第1期62-64,共3页
Mycorrhizal and N-fixing root symbioses evolved at two points in the past when global CO_(2)was highest,consistent with the high demand these symbioses place on host C.Trees hosting both mycorrhiza and N-fixing bacter... Mycorrhizal and N-fixing root symbioses evolved at two points in the past when global CO_(2)was highest,consistent with the high demand these symbioses place on host C.Trees hosting both mycorrhiza and N-fixing bacteria are able to fix more atmospheric CO_(2)and grow at faster rates than non-symbiotic plants,or plants with only mycorrhiza.We argue that on the basis of this improved C capture,N-fixing trees act as C-pumps,sequestering C and locking it in biomass,thus,if properly managed,can contribute significantly towards the mitigation of rising CO_(2)levels. 展开更多
关键词 ROOT (2) PROPERLY
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MRCKα is a novel regulator of prolactin-induced lactogenesis in bovine mammary epithelial cells 被引量:2
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作者 Fang Wang Jürgen van Baal +3 位作者 Lu Ma Xuejun Gao Jan Dijkstra Dengpan Bu 《Animal Nutrition》 SCIE CSCD 2022年第3期319-328,共10页
Myotonic dystrophy-related Cdc42-binding kinase alpha(MRCKα)is an integral component of signaling pathways controlling vital cellular processes,including cytoskeletal reorganization,cell proliferation and cell surviv... Myotonic dystrophy-related Cdc42-binding kinase alpha(MRCKα)is an integral component of signaling pathways controlling vital cellular processes,including cytoskeletal reorganization,cell proliferation and cell survival.In this study,we investigated the physiological role of MRCKα in milk protein and fat production in dairy cows,which requires a dynamic and strict organization of the cytoskeletal network in bovine mammary epithelial cells(BMEC).Within a selection of 9 Holstein cows,we found that both mRNA and protein expression of MRCKα in the mammary gland were upregulated during lactation and correlated positively(r>0.89)with the mRNA and protein levels of b-casein.Similar positive correlations(r>0.79)were found in a primary culture of BMEC stimulated with prolactin for 24 h.In these cells,silencing of MRCKα decreased basal b-casein,sterol-regulatory element binding protein(SREBP)-1 and cyclin D1 protein level,phosphorylation of mTOR,triglyceride secretion,cell number and viabilitydwhile overexpression of MRCKα displayed the reversed effect.Notably,silencing of MRCKα completely prevented the stimulatory action of prolactin on the same parameters.These data demonstrate that MRCKα is a critical mediator of prolactin-induced lactogenesis via stimulation of the mTOR/SREBP1/cyclin D1 signaling pathway. 展开更多
关键词 Myotonic dystrophy-related Cdc42-binding kinase alpha Bovine mammary gland PROLACTIN Mechanistic target of rapamycin Sterol regulatory element-binding protein-1 Cyclin D1
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The sooty moulds 被引量:8
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作者 Putarak Chomnunti Sinang Hongsanan +8 位作者 Begoña Aguirre-Hudson Qing Tian Derek Peršoh Manpreet K.Dhami Aisyah S.Alias Jianchu Xu Xingzhong Liu Marc Stadler Kevin D.Hyde 《Fungal Diversity》 SCIE 2014年第3期1-36,共36页
Sooty moulds are a remarkable,but poorly understood group of fungi.They coat fruits and leaves superficially with black mycelia,which reduces photosynthesis rates of host plants.Few researchers have,however,tried to q... Sooty moulds are a remarkable,but poorly understood group of fungi.They coat fruits and leaves superficially with black mycelia,which reduces photosynthesis rates of host plants.Few researchers have,however,tried to quantify their economic importance.Sooty moulds have been well-studied at the morphological level,but they are poorly represented in a natural classification based on phylogeny.Representatives are presently known in Antennulariellaceae,Capnodiaceae,Chaetothyriaceae,Coccodiniaceae,Euantennariaceae,Metacapnodiaceae and Trichomeriaceae and several miscellaneous genera.However,molecular data is available for only five families.Most sooty mould colonies comprise numerous species and thus it is hard to confirm relationships between genera or sexual and asexual states.Future studies need to obtain single spore isolates of species to test their phylogenetic affinities and linkages between morphs.Next generation sequencing has shown sooty mould colonies to contain many more fungal species than expected,but it is not clear which species are dominant or active in the communities.They are more common in tropical,subtropical and warm temperate regions and thus their prevalence in temperate regions is likely to increase with global warming.Sooty moulds are rarely parasitized by fungicolous taxa and these may have biocontrol potential.They apparently grow in extreme environments and may be xerophilic.This needs testing as xerophilic taxa may be of interest for industrial applications.Sooty moulds grow on sugars and appear to out-compete typical“weed”fungi and bacteria.They may produce antibiotics for this purpose and their biochemical potential for obtaining novel bioactive compounds for medical application is underexplored. 展开更多
关键词 ANTIBIOTICS CAPNODIALES CHAETOTHYRIALES Global warming Life cycle PHYLOGENY Xerophiles
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Estimating landscape susceptibility to soil erosion using a GIS-based approach in Northern Ethiopia 被引量:1
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作者 Lulseged Tamene Zenebe Adimassu +1 位作者 Ermias Aynekulu Tesfaye Yaekob 《International Soil and Water Conservation Research》 SCIE CSCD 2017年第3期221-230,共10页
Soil erosion is a very critical form of land degradation resulting in the loss of soil nutrients and downstream sedimentation of water storages in the highlands of Ethiopia.As it is technically and financially impossi... Soil erosion is a very critical form of land degradation resulting in the loss of soil nutrients and downstream sedimentation of water storages in the highlands of Ethiopia.As it is technically and financially impossible to conserve all landscapes affected by erosion,identification of priority areas of intervention is necessary.Spatially distributed erosion models can help map landscape susceptibility to erosion and identify high erosion risk areas.Integration of erosion models with geographic information systems(GIS)enables assessing evaluate the spatial variability of soil erosion and plan implementing conservation measures at landscape levels.In this study,the Revised Universal Soil Loss Equation adjusted for sediment delivery ratio was used in a GIS system to assess landscape sensitivity to erosion and identify hotspots.The approach was applied in three catchments with size being 10–20 km^(2) and results were compared against quantitative and semi-quantitative data.The model estimated mean soil loss rates of about 45 t ha^(−1) y^(−1) with an average variability of 30%between catchments.The estimated soil loss rate is above the tolerable limit of 10 t ha^(−1) y^(−1).The model predicted high soil loss rates at steep slopes and shoulder positions as well as along gullies.The results of the study demonstrate that knowledge of spatial patterns of high soil loss risk areas can help deploy site-specific conservation measures. 展开更多
关键词 Revised universal soil loss equation Sediment delivery ratio Hot-spot areas WATERSHED Sediment deposition
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Climate change in Central Asia:Sino-German cooperative research findings 被引量:8
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作者 Yang Yu Xi Chen +16 位作者 Markus Disse Bernd Cyffka Jiaqiang Lei Haiyan Zhang Andreas Brieden Martin Welp Jilili Abuduwaili Yaoming Li Fanjiang Zeng Dongwei Gui Niels Thevs Zhijie Ta Xin Gao Yuanyue Pi Xiang Yu Lingxiao Sun Ruide Yu 《Science Bulletin》 SCIE EI CAS CSCD 2020年第9期689-692,M0003,共5页
Central Asia(CA)occupies the hinterland of the Eurasian continent,containing the countries of Uzbekistan,Kyrgyzstan,Turkmenistan,Tajikistan,and Kazakhstan[1,2].Being isolated by the Pamir Mountains in Tajikistan,the T... Central Asia(CA)occupies the hinterland of the Eurasian continent,containing the countries of Uzbekistan,Kyrgyzstan,Turkmenistan,Tajikistan,and Kazakhstan[1,2].Being isolated by the Pamir Mountains in Tajikistan,the Tibetan Plateau and the Tian Shan Mountains on the border between China and Kyrgyzstan. 展开更多
关键词 气候变化 MOUNTAINS Eurasian
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